Method of servicing wells using a curved conduit



April 28, 1970 w. F. BOHLMANN, JR, ETAL METHOD OF SERVICING WELLS USING A CURVED CONDUIT Filed 00".. 18. 1967 1 R R 7 m 2 w w m M n M 5 in 1 2 f A mum a LA 7 k 4 am 3 u w i w LA JW wmm MG wi m3] 1&mm 2 M M W Hmw m m h HlV Y s Ft NA 2 WT PI/ A mm w m N l O m 2 2 2 m E Tx 1 x X i fi f 2 l l 1/ G m m n u v. a F D FIG. I.

April 1970 w. F. BOHLMANN, JR,, ET AL 3,508,614

METHOD OF SERVICING WELLS USING A CURVED CONDUIT 2 Sheets-Sheet 2 FIG. 6.

Filed Oct. 18. 1967 FIG. 4.

FIG.7.

. INVENTORS.

CHARLES B. CORLEY, JR WILLY F. BOHLMANN,JR.,

BY JEROME DGOODRICH JR A a:

FIG. IA.

United States Patent O 3,508,614 METHOD OF SERVICING WELLS USING A CURVED CONDUIT Willv F. Bohlmann, Jr., New Plymouth, North Island,

New Zealand, Jerome D. Goodrich, Jr., Kenner, La.,

and Charles B. Corley, Jr., Houston, Tex., assignors to Esso Production Research Company Filed Oct. 18, 1967, Ser. No. 676,323 Int. Cl. E21b 43/00, 43/01 U.S. Cl. 166315 Claims ABSTRACT OF THE DISCLOSURE Workover operations are performed in wells having a curved conduit such as a submarine well having a radius bend at the wellhead by introducing into the conduit a segmented tubular member such as a tool and running the tubular member through said conduit solely by fluid pressure exerted thereagainst, a substantial portion of the length of the tubular member being maintained free of contact with the inner wall of the conduit to extend the life of the tubular member and reduce the pressure required to run it in.

BACKGROUND OF THE INVENTION Field of the invention The present invention is directed to method and apparatus for servicing wells. More particularly, the invention is concerned with the servicing of wells completed on water bottom. In its more specific aspects, the invention is concerned with the servicing of wells having a conduit which has at least a portion of its length described a curve.

DESCRIPTION OF THE PRIOR ART It is known to run flexible tubular members into wells having a curved conduit. Flexible tubular members may kink or corkscrew in a well and present considerable problems in their use. It is also known to run substantially inflexible tubular members into such wells. However, when such is done, there is danger of the tubular member experiencing a considerable amount of friction drag when it is caused to travel through curved pipes and the like. The present invention avoids such problems and presents only a small area for contact with the inner wall of the curved pipe.

SUMMARY OF THE INVENTION The present invention may be briefly described and summarized as a method for servicing a well which has a curved conduit therein in which there is introduced into the conduit a segmented, elongated tubular member. The segmented, elongated tubular member is run through the conduit solely by fluid pressure applied against said tubular member from a remote point. As the tubular member is run through the curved conduit, a substantial portion of its length is maintained free from contact with the inner wall of the conduit such that the life of the tubular member is extended and the pressure required to run the tubular member is reduced. The life of the tubular member is extended and it is because the tubular member is not worn by excessive contact with the inner wall of the conduit. Likewise, by virtue of minimizing the contact, the pressure required to run the tubular member is reduced.

The invention is also directed to a tubular member which is adapted to be moved through a curved conduit. The tubular member comprises first and second elongated rigid pipe sections in which coupling means including means connecting the pipe sections for angular movement of the first section relative to the second section is provided to form a continuous fluid passageway between the Patented Apr. 28, 1970 "Ice BRIEF DESCRIPTION OF THE DRAWING The present invention will be further described and illustrated by reference to the drawing in which FIG. 1A is a view of a cased well completed on water bottom having a plurality of curved conduits leading therein;

FIG. 1 is a cross-sectional view of the well showing the interconnected conduits or tubing strings and having an elongated tubular member run therein;

FIG. 2 illustrates the elongated tubular member seated in one of the conduits or tubing strings;

FIG. 3 shows the removal of the elongated tubular conduit;

FIG. 4 is a detail of the coupling and connecting means of the elongated tubular conduit;

FIG. 5 is another embodiment of the coupling and connecting means;

FIG. 6 is a modification of the coupling and connecting means of FIG. 5, and;

FIG. 7 is another coupling and connecting means in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODI- MENTS RELATIVE TO THE DRAWINGS Referring now to the drawings and particularly to FIG. 1A to FIG. 3 in which identical numerals designate identical parts, numeral 11 designates a body of water having a well 12 drilled from water bottom 13. Arranged in the Well 12 is a casing 14 which is cemented in place with cement 15. The casing 14 is closed by a wellhead 16 from which extends curved conduits or tubular members 17 and 18 which lead to water surface or to the shore from whence fluids may be introduced into the conduits 17 or 18 or fluid discharged therefrom. Referring now to FIGS. 1A-3, specifically, the casing 14 is cemented with cement 15 and the tubing 17 and 18 are shown as being interconnected by a passageway 23. The tubing 18 is provided with a polished bore nipple 19 and a landing nipple 20. Introduced down the tubing 18 from water surface (such as a platform or vessel) or the shore (not shown) is a segmented, elongated tubular member 21 comprised of rigid pipe sections 22 interconnected by coupling members 24.

In FIG. 1 the elongated tubular member 21 is shown in the running in position with fluid flowing down through the conduit 18. In FIG. 2, the elongated tubular member 21 is shown in position in the polished bore nipple 19 and the landing nipple 20. In this position, the elongated tubular member may be used for conducting squeezing, cementing, acidizing and other oil or gas field operations such as work-over operations including removing sand and the like. Thus, these operations may be conducted by flowing fluid down through the tubing or conduit 18 and through the elongated tubular member 21. As shown in FIG. 2, the passageway 23 is sealed ofif by sealing means carried by the elongated tubular member 21.

Referring now to FIG. 2, when it is desired to remove the elongated tubular member 21, the perforations 25 in the lower end of the conduit or tubing 17 may be closed by depositing in the conduit 17 an acid dissolvable material which suitably may be particles of calcium carbonate. The calcium carbonate may be in a finely divided form such that it will impede flow through the perforations 25 sufficient to allow fluid to be flowed down through 3 the tubing 17 through the passageway 23 and against the elongated tubular member 21. In the instance of FIGS. 2 and 3, a body 26, which suitably is particulate, of an acid dissolva'ble material such as particles of calcium carbonate, aluminum, and the like is deposited in the tubular member 17. Thereafter fluid is flowed downwardly through the tubing 17 and upwardly in the tubing 18 against a suitable pulling tool 27 which latches to the tubular member 21. The tubular member 21 is then released from the polished bore nipple 19 and land ing nipple 20 and then proceeds upwardly to the surface of the water or to shore through the tubing or conduit 18.

In the mode described with respect to FIGS. 1A-3, the

elongated tubular member 21 is placed and removed solely by the use of pressure applied through the conduits 17 and 18.

Referring now to FIG. 4, a coupling member 24 is provided with a knuckle joint having a threaded pipe stub 31 adapted to connect to rigid pipe sections such as 22. The knuckle joint 30 encloses a connecting means 32 which is sealed by sealing member 33 to prevent discharge of fluid. The connecting means 32 has a pipe stub 34 which is adapted to connect to the rigid pipe sections 22. The stub 34 is arranged to move through an opening 35 and the knuckle joint 30 which allows relative movement of the pipe sections 22 with respect to each other.

Referring now to FIG. 5, a coupling member such as 24 is comprised of a connecting means which suitably may be a hose material which may be constructed of a deformable material such as synthetic rubber and the like or which may be a metallic hose. In any event, the connecting means 40 is connected such as by threaded means 41 to rigid pipe sections 22. The coupling means 24 is suitably an outer coupling acting as a tension or compression member 'by bearing on spaced apart shoulders 42, 43, 44 and 45. The coupling means 24 is suitably a cylindrical member closed on each end by a plate member 46 having axial openings 47 on each end thereof through which the rigid pipe sections 22 extend. By virtue of the shoulders 42, 43, 44, and and the hose 40 relative movement is provided between the rigid pipe sections 22.

A modification of FIG. 5 is shown in FIG. 6 wherein the hose 40 is replaced by a metal bellows 50. Otherwise, FIG. 6 is similar to FIG. 5.

In FIG. 7, the rigid pipe sections 22 are interconnected by a steel insert 60 which extends into the ends of the pipe sections 22. The steel insert has a shoulder 61 on one end and a shoulder 62 on the other end. These shoulders 61 and 62 are sealed respectively by a sealing means 63 and 64 with the inner Wall of the rigid pipe sections 22. Internal stops or shoulders 64 and 65 limit the relative movement of the insert 60. Compressible packing means 66 and 67 are arranged between the shoulders 61 and 62 and the inner walls of the rigid pipe sections 22. In this embodiment, it will be seen that rigid pipe sections 22 have an inwardly directed shoulder 68 and axial opening 69 through which the steel insert extends. Wear surfaces such as shoulders 70 and 71 are provided to protect the pipe sections 22. Thus, in the embodiment of FIGS. 5, 6 and 7, the rigid pipe sections have relative movement but yet the rigid pipe sections are protected and spaced from contact with the inner wall of the tubular members such as 17 and 18.

The present invention is quite important and useful and in fact has been used successfully. A tubing extension constructed in accordance with the present invention considerably reduces the friction drag in traversing a five foot radius bend in contrast to a continuously flexible tubing extension such as a metal or deformable hose. In one operation, feet of a segmented aluminum tubing 4 extension in accordance with the present invention was run in a well and encountered no difiiculty due to friction drag. When a continuously flexible aluminum tubing extension member was run, excessive wear on the continuously flexible tubing extension member resulted. In other words, the present invention allows a well to be serviced with a segmented tubular extension member without encountering the difliculties heretofore encountered such as excessive wear due to excessive friction. Heretofore, excessive forces were required to run such continuously flexible members.

The present invention is quite important and useful in that the segmented tubular member avoids all the difliculties heretofore encountered with flexible or convoluted pipe.

The present invention avoids excessive wear and friction and provides a new method and apparatus which overcomes the difiiculties of the prior art.

The present invention is quite useful in underwater operations where a plurality of tubing strings is required. One tubing string is used for conducting well operations whereas the other tubing string is employed for servicing operations so that there is a circulatory path for fluid. The present invention allows such well operations to be conducted by fluid pressure and avoids the use of wirelines heretofore necessary.

The nature and objects of the present invention having been completely described and illustrated and the best mode and embodiment thereof contemplated set forth what we wish to claim as new and useful and secure by Letters Patent is:

1. A method for servicing a well provided with a conduit having at least a portion of its length describing a curve which comprises:

introducing into said conduit a segmented, elongated tubular member formed of rigid pipe sections,

running said tubular member in both directions through said conduit solely by fluid pressure applied against said tubular member,

maintaining a substantial portion of the length of said tubular member free from contact with the inner wall of said conduit as said tubular member is run through said conduit, and flowing fluid through said tubular member to perform an oil or gas field operation in said well,

whereby the life of said tubular member is extended and the pressure required to run said tubular member is reduced.

2. A method in accordance with claim 1 in which the fluid pressure is applied from a remote point.

3. A method in accordance with claim 1 in which said fluid is flowed through said tubular member after it has been run.

4. A method in accordance with claim 3 in which said tubular member is run upwardly through said conduit solely by fluid pressure applied against said tubular member subsequent. to flow of said fluid through said tubular member.

5. A method in accordance with claim 1 in which said tubular member is then run upwardly through said conduit solely by fluid pressure.

References Cited UNITED STATES PATENTS 2,810,442 10/1957 Tausch 166--156 3,003,560 10/1961 Corley et a1. 16670 3,090,440 5/1963 Lagucki 1660.5 X 3,367,421 2/1968 Raulins 166-153 STEPHEN J. NOVOSAD, Primary Examiner 

